The light emitting diode (LED) is a solid-state semiconductor light-emitting device, which is widely used in lighting applications such as signage and displays.
Many LED epitaxial wafers are obtained from the metal-organic chemical vapor deposition (MOCVD) process, the process of which is described as follows: put the epitaxial wafer substrate (e.g., sapphire substrate) on the pocket profile of the graphite wafer carrier and transmit to the MOCVD reaction chamber together with the graphite wafer carrier.
The substrate, together with the graphite wafer carrier, is heated to about 1000° C. Input meta-organic compound and Group V gas in the reaction chamber. After high-temperature pyrolysis, rejoin the LED epitaxial layer on the wafer substrate.
In the LED epitaxial wafer process, the wafer substrate is directly carried on the graphite wafer carrier. Therefore, the graphite wafer carrier structure has an important influence on the epitaxy yield, which is a key point for industrial study.